Inhibitors of Src kinase for use in alzheimer&#39;s disease

ABSTRACT

The present invention relates to the identification of inhibitors of Src kinase, assays and methods useful for such identification and the use of Src inhibitors for the preparation of pharmaceuticals for the treatment of Alzheimer&#39;s disease.

[0001] The present invention relates to the identification of inhibitors of Src kinase, assays and methods useful for such identification and the use of Src inhibitors for the preparation of pharmaceuticals for the treatment of Alzheimer's disease.

[0002] Alzheimer's disease is a neurodegenerative disorder of the brain, which is accompanied at the cellular level by a massive loss of neurons in the limbic system and in the cerebral cortex. In the brain areas affected, protein deposits, so-called plaques, can be detected at the molecular level, which are an essential characteristic of Alzheimer's disease. The protein occurring most frequently in these plaques is a peptide of 40 to 42 amino acids in size, which is designated as Aβ-peptide. This peptide is a cleavage product of a larger protein of 695 to 770 amino acids, the so-called Amyloid Precursor Protein (APP).

[0003] APP is an integral transmembrane protein, which firstly traverses the lipid, bilayer. By far the largest part of the protein is extracellular, while the shorter C-terminal domain is directed into the cytosol (FIG. 1). APP is the substrate of three different proteases: α-secretase, β-secretase and γ-secretase. Within APP, about two thirds of the Aβ-peptide originates from the extracellular domain and about one third from the transmembrane domain.

[0004] Beside the membrane-linked APP, a secreted form of APP can be detected which consists of the large ectodomain of APP and is designated as APP_(sec) (“secreted APP”). APP_(sec) is formed from APP by proteolytic cleavage, which is effected by the α-secretase (FIG. 2). This proteolytic cleavage takes place within the amino acid sequence of the Aβ-peptide (after amino acid residue 16 of the Aβ-peptide). Proteolysis of APP by the α-secretase thus excludes the formation of the Aβ-peptide.

[0005] The Aβ-peptide can thus only be formed from APP in an alternative processing route. It is postulated that two proteases are involved in this processing, one protease, which is designated as β-secretase, cleaving at the N-terminus of the Aβ-peptide in the APP and the second protease, which is designated as γ-secretase, releasing the C-terminus of the Aβ-peptide (Kang, J. et al., (1987) Nature, 325, 733 (FIG. 2).

[0006] There are many indications that the Aβ-peptide is a crucial factor in the occurrence of Alzheimer's disease. Inter alia, neurotoxicity of Aβ-fibrils in cell culture is postulated (Yankner, B.A. et al., (1990) Proc Natl Acad Sci USA, 87, 9020). In patients with Down's syndrome, in which APP occurs in an additional copy, the neuropathology characteristic of Alzheimer's disease also occurs even at an age of 30 years. Here, it is assumed that the overexpression of APP follows an increased conversion into the Aβ-peptide (Rumble, B. et al., (1989), N. Engl. J. Med., 320, 1446).

[0007] Furthermore the strongest indication of the central role of the Aβ-peptide in Alzheimer's disease are the familial forms of the disease. Here, mutations are found in the APP gene around the area of the secretase cleavage sites or in two further AD-associated genes (presenilins), which in cell culture lead to a significant increase in Aβ production (Scheuner, D. et al., (1996), Nature Medicine, 2, 864).

[0008] There are a number of indications that APP is first cleaved by the β-secretase, to serve thereafter as a substrate for γ-secretase (Maruyama, K. Y. et al., (1994) Biochem. Biophys Res Commun, 202, 1517; Estus, S. et al., (1992), Science, 255, 726). The γ-secretase therefore has a crucial role in the formation of the Aβ-peptide. A demonstration of the activity of the γ-secretase which is customarily used is the detection of the Aβ-peptide, which, however, frequently turns out to be difficult.

[0009] An important reason for this is that only a small part of APP is converted into the Aβ-peptide (Simons M, et al., Neurosci (1996) 1;16(3):899-908). Moreover, the Aβ-peptide is a small breakage fragment of about 4 kDa and, on account of its hydrophobic character, has a great tendency to self-aggregation so that it easily precipitates under physiological conditions (Hilbich, C. et al., (1991) J. Mol. Biol., 218, 149).

[0010] The short, 47 amino acid-long C-terminal tail of APP is exposed to the cytosol and is the site of interaction for molecular adaptors containing PTB domains, named Fe65, X11, m-dab and Jip1. Since the binding of these proteins is dependent on the YENPTY sequence on APP, it is expected that their interactions are not simultaneous (T. Russo et al. (1998) FEBS Left. 434-1-7; N. Zambrano et al. (1997) J. Biol. Chem. 272, 6399-6405). Indeed, it has been shown, in cultured cells, that Fe65 and X11 proteins have opposite effects on the proteolytic processing of APP (Sabo S. et al. (1999) J. Biol. Chem. 274, 7952-7957; Borg J.P. et al. (1998) J. Biol. Chem. 273, 14761-14766). A possible explanation for these findings may reside in the recruitment, by either Fe65 or X11, of APP in different macromolecular complexes, depending on the interaction of different sets of proteins with the other protein-protein interaction domains of the two adaptors.

[0011] The APP cytodomain contains various serine and threonine residues, which are phosphorylated in vitro by different kinase activities. Thr668 is a main site of phosphorylation in vivo, being phosphorylated by neuronal cyclin-dependent kinases, Cdk5 in neurons (lijima, K. et al. (2000) J. Neurochem. 75, 1085-1091), cdc2 kinase in dividing cells (Suzuki, T. et al. (1994) EMBO J. 13, 1114-1122; Oishi, M. et al. (1997) Mol. Med. 3, 111-123), and glycogen synthase kinase 3b (GSK3b) and stress-activated protein kinase 1b (SAP kinase1b) in vitro (Aplin, E. E. et al. (1996) J. Neurochem. 67, 699-707; Standen, C. L. et al. (2001) J. Neurochem. 76, 316-320). It has been shown that phosphorylation of APP regulates neurite extension in differentiating PC12 cells (Ando, K. et al. (1999) J. Neurosci. 19, 4421-4427), while, at the molecular level, APP phosphorylation may regulate the binding to the PTB domain-containing adaptors and its processing (Ando K. et al. (2001) J Biol. Chem., 276, 40353-40361).

[0012] Previously it was demonstrated that APP is phosphorylated at tyrosine 682 in cells expressing an active form of the Abl non receptor tyrosine kinase (Zambrano N. et al. (2001) J Biol. Chem. 276, 19787-92); active Abl is recruited in proximity to APP by Fe65, which may bind simultaneously these two proteins through its WW domain (Abl) and PTB2 domain (APP). Phosphorylation of Tyr682 of APP generates a docking site for the SH2 domain of Abl and, in fact stable complexes between APP and Abl are formed.

[0013] In order to test the hypothesis that tyrosine phosphorylation regulates pp60c-src biological activity, Kmiecik and Shalloway (1987) Cell 49, 65-73 described the construction and study of pp60c-src mutants in which Tyr 527 and Tyr 416 were separately or coordinately altered to phenylalanine. Tyr—Phe 527 mutation strongly activated pp60c-src transforming and kinase activities, whereas the additional introduction of a Tyr—Phe 416 mutation suppressed these activities. Tyr—Phe 416 mutation of normal pp60c-src eliminated its partial transforming activity, which suggests that transient or otherwise restricted phosphorylation of Tyr 416 is important for pp60c-src function even though stable phosphorylation is not observed in vivo. Normally, pp60c-src is phosphorylated in vivo at tyrosine 527, a residue not present in pp60v-src (its transforming homolog), and not at tyrosine 416, its site of in vitro autophosphorylation.

[0014] Williamson et al. (2002) J. Neurochem. 22, 10-20) described the rapid phosphorylation of neuronal proteins including Tau and Focal adhesion kinase in response to amyloid-β peptide exposure and an involvement of Src family protein kinases.

[0015] Slack, B. E. and Berse; B. (1998) described in Society for Neuroscience Abstracts, Vol. 24, No. 1-2, pp. 208 (Conference/Meeting Information: 28^(th) Annual Meeting of the Society for Neuroscience, Part 1, Los Angeles, Calif., USA, Nov. 7-12, 1998 Society for Neuroscience, ISSN: 0190-5295) a role for tyrosine kinases in the stimulation of APP release by action of muscarinic m3 acetylcholine receptors. They described a role for Src tyrosine kinase in the regulation of APP_(sec) release by muscarinic receptors. They demonstrated that an increase in the active form of Src leads to a decrease in secAPP.

[0016] The present invention provides methods of identifying therapeutic agents for the treatment of Alzheimer's disease.

[0017] One embodiment of the invention provides methods for identifying inhibitors of Src activity, whereby the methods comprise the steps

[0018] a) providing a Src protein (i.e. a Src encoding DNA under control of an expression element) and

[0019] b) determining if a compound inhibits the activity of Src.

[0020] The Src protein could be any mammalian Src protein, preferably human Src (SEQ ID NO. 1 (isoform 1) and SEQ ID NO. 2 (isoform 2)) or rodent Src (SEQ ID NO. 3). The protein could be obtained by expressing human Src or rodent Src cDNA, by using e. g. sequences SEQ ID NO. 4 or SEQ ID NO. 5. In addition, one of the sequences deposited under Genbank Accession No. M17031 or BC011566 can be used.

[0021] For the method preferably a mammalian cell or cell line is used in which Src is expressed, either naturally or because the cell/cell line is genetically engineered. In a particular embodiment primary cultures of neurones are used.

[0022] Another embodiment of the invention relates to a method of identifying compounds, which inhibit Src expression. The method comprises the steps

[0023] a) providing a sequence which regulates Src expression (i.e. a Src promotor sequence) and

[0024] b) determining if a compound inhibits the expression of Src protein.

[0025] The sequence which regulates Src expression is preferably linked to a reporter gene or a reporter gene construct. Such reporter gene can easily be used to determine, if a compound inhibits the expression of Src. Another possibility is the use of the Src gene. The region of chromosome 20 including the Src gene is deposited under Genbank Accession no AL133293.

[0026] An house-keeping promoter, which can be used as a sequence which regulates Src expression, has been described, as well as an alternative promoter regulated by the Hepatic Nuclear Factor-1 a (Bonham et al. (2000) J. Biol. Chem. 275, 37604) (Genbank accession number AF272982).

[0027] Active compounds, this means compounds, which inhibit Src expression or which inhibit Src protein activity, can be used as pharmaceuticals. Such compounds can be used for the preparation of a pharmaceutical for the treatment or prevention of Alzheimer's disease.

[0028] Another embodiment of the invention relates to the use of compounds identified by one of the forgoing methods for preparing a pharmaceutical for the treatment of Alzheimer's disease.

[0029] The invention further relates to a method of preparing a pharmaceutical for treatment of Alzheimer's disease comprising the steps

[0030] a) identification of a therapeutic compound by the use of one of the methods described above;

[0031] b) optimisation of the identified compound; and

[0032] c) formulation of the optimised compound.

[0033] Another embodiment of the invention relates to the use of Src inhibitors known in the art for the preparation of a pharmaceutical for the treatment or the prevention of Alzheimer's disease. The invention relates to the use of PP2 (4-amino-5-(4-chlorophenyl)-7-(t-butyl)pyrazolo[3,4d]pyrimidine) as pharmaceutical. The invention further relates to the use of PP2 for the preparation of a pharmaceutical for the treatment of Alzheime'rs disease.

[0034] Another embodiment of the invention refers to the use of PP2 for the preparation of a pharmaceutical for the treatment of Alzheimer's disease.

[0035] The new results demonstrate, that APP is phosphorylated not only by Abl. In fact Src kinase is also responsible for APP tyrosine phosphorylation. It is expected that tyrosine phosphorylation of APP alters the binding properties of its cytodomain, and then the processing of APP could be consequently modified. If so, this will prove useful the use of currently available tyrosine kinase inhibitors, and to design new ones for pharmacological modulation of the release of APP processing products in cellular and animal models of Alzheimer's disease.

[0036] Taken together, the results from the following examples suggest that exogenous Src activity is responsible for activation of a pathway resulting in increased Aβ secretion. This also suggests that PP2 could be used as a pharmacological agent able to reduce Aβ secretion in cellular and animal systems resembling AD status.

[0037] Therefore, a line of CHO cells stably overexpressing APP751 form was used, which secretes discrete levels of Aβ. If secretion involves endogenous Src activity, PP2 should be able to inhibit production of Aβ also in this cellular system. This is indeed the case since, as shown in FIG. 6, PP2 reduces in a dose-dependent manner the amount of Aβ at the three time points tested (1, 3 and 12 hours), while PP3, used at the highest concentration, has no effect.

[0038] These experiments clearly outline the relevance of Src activation in Aβ secretion and constitute the basis to try pharmacological applications for tyrosine kinase inhibitors in the treatment of AD. Screening of such inhibitors and their optimization will lead to the development of potential, innovative therapeutic agents for treatment of Alzheimer's disease.

EXAMPLES Example 1

[0039] Cell Culture, Transfections and Treatments

[0040] Human embryonic kidney cells (HEK293) were cultured in Dulbecco's modified minimal medium supplemented with 10% fetal calf serum at 37° C. in a 5% CO₂ atmosphere. For transfection, cells were grown for 16 hours in antibiotic-free medium, and transfected with Lipofectamine 2000 (Invitrogen) according to manufacturer's instructions. The total amount of DNA was maintained constant by addition of empty vector DNA. 48 hours after transfection, culture medium were recovered, while cells were harvested in ice-cold phosphate buffer saline (PBS) and gently lysed in lysis buffer (50 mM Tris/HCl, pH 7.5, 150 mM NaCl, 0.5% Triton X-100, 10% glycerol, 50 mM NaF, 1mM Na vanadate), in the presence of a protease inhibitor cocktail (Complete, EDTA-free, Roche). The extracts were clarified by centrifugation at 16,000×g at 4° C., and the protein concentration determined by the Bio-Rad protein assay according to manufacturer's instructions. For metabolic labelling, 36 hours after transfection, cells were incubated for 30 minutes in medium without methionine and cysteine, then the medium was replaced with fresh medium containing 80 μCi/ml of ³⁵S-methionine/cysteine mixture (Promix, 1000 Ci/mmol, Amersham Pharmacia Biotech). Pulse was for 30 minutes, then the radioactive medium was replaced with complete medium for 90 minutes. CHO cells expressing wild-type APP751 have been described (N. Zambrano et al. (1997) J. Biol. Chem. 272, 6399-6405). Immuno-precipitations were performed either on culture medium, or on cellular lysates with 1 μg/sample of the 6E10 monoclonal antibody (Signet). Radioactive samples were resolved on 10% SDS-PAGE and quantitated with a Storm 840 phosphorimager (Amersham Pharmacia Biotech). PP2 and PP3 (Hanke, J.H. et al. (1996) J. Biol. Chem. 271, 695-701) were purchased from Calbiochem and dissolved in DMSO; treatments were performed on transfected cells for 48 hours with vehicle alone, or with 1, 5 and 20 μM PP2 or PP3. Concentration of DMSO was the same in all samples. Treatments on CHO/APP751 cells was made with DMSO, or PP2 (5 and 20 μM), or PP3 (20 μM).

Example 2

[0041] HEK293 cells were transfected with APP695 expression vectors. This cellular system was used because these cells are transfected to high efficiency, and because they express the whole set of processing activities required for APP maturation. In fact, upon transfection of human APP695 expression vectors, both α-secretase product (APP_(sec)) and β-γ-secretase products (βP) accumulate in the culture medium. HEK293 cells were co-transfected with APP and either empty vector, or active Abl (Abl-PP), or active Src (SrcYF) kinases, and the secretion of APP_(sec) and β were evaluated. Transfected cells have been pulse-labelled with ³⁵S-Met/Cys mix for 30′, and chased with cold amino acids for 90′. Both medium and protein extracts have been used in immunoprecipitation experiments for quantitative dosage of radiolabeled APP_(sec) and holo-APP, respectively. While the stability of holo-APP was not affected by co-transfection with either Abl-PP or SrcYF active kinases (FIG. 3A), a reduction in the relative amounts of APP_(sec), normalised to the corresponding holo-APP synthesised during the pulse period was observed in both cases (FIG. 3B). This can be interpreted as a decrease of the activity of the α-secretase pathway upon co-transfection of APP with the active kinases.

Example 3

[0042] Next, the accumulation of Aβ from cells transfected as above was investigated. The dosage was performed by sandwich ELISA assays on culture medium at 48 hours after transfection (FIG. 4). The assay clearly shows that in Src-expressing cells the amount of Aβ secreted is more elevated than in the presence of the control vector, or Abl-PP. The mechanism by which active Src elicits such a dramatic increase in Aβ secretion is not clear. However, it might depend on phosphorylation of some other proteins, different from APP, since tyrosine phosphorylation of APP by Abl-PP does not result in increased Aβ levels. Accordingly, a similar behaviour is obtained with various APP mutants bearing tyrosine substitutions to either glycine or phenylalanine (data not shown). Anyway, the rise in Aβ levels does depend on the tyrosine kinase activity of Src, since the accumulation of Aβ is sensitive to treatment by the Src-family specific inhibitor PP2. In fact, as shown in FIG. 5, the exposure of transfected cells for 48 hours to increasing concentrations of PP2 results in dose-dependent decrease of secreted AP. Either PP3, an inactive analog of PP2, or vehicle alone, do not affect Aβ rise by SrcYF transfection.

[0043] Taken together, these observations suggest that exogenous Src activity is responsible for activation of a so far unidentified pathway resulting in increased Aβ secretion.

REFERENCES

[0044] 1) T. Russo et al. (1998) FEBS Left. 434,1-7.

[0045] 2) N. Zambrano et al. (1997) J. Biol. Chem. 272, 6399-6405.

[0046] 3) Sabo S. et al. (1999) J. Biol. Chem. 274, 7952-7957.

[0047] 4) Borg J.P. et al. (1998) J. Biol. Chem. 273, 14761-14766.

[0048] 5) lijima, K. et al. (2000) J. Neurochem. 75, 1085-1091.

[0049] 6) Suzuki, T. et al. (1994) EMBO J. 13, 1114-1122.

[0050] 7) Oishi, M. et al. (1997) Mol. Med. 3, 111-123.

[0051] 8) Aplin, E. E. et al. (1996) J. Neurochem. 67, 699-707.

[0052] 9) Standen, C. L. et al. (2001) J. Neurochem. 76, 316-320.

[0053] 10) Ando, K. et al. (1999) J. Neurosci. 19, 4421-4427.

[0054] 11) Ando K. et al. (2001) J Biol Chem.;276, 40353-40361.

[0055] 12) Zambrano N. et al. (2001) J Biol Chem 276, 19787-19792.

[0056] 13) Hanke, J.H. et al. (1996) J. Biol. Chem. 271, 695-701. TABLE 1 Protein sequence of isoform 1 of human Src protein (SEQ ID NO. 1) MGSNKSKPKDASQRRRSLEPAENVHGAGGGAFPASQTPSKPASADGHRGPSAAFAPAAA EPKLFGGFNSSDTVTSPQRAGPLAGGVTTFVALYDYESRTETDLSFKKGERLQIVNNTRKVD VREGDWWLAHSLSTGQTGYIPSNYVAPSDSIQAEEWYFGKITRRESERLLLNAENPRGTFL VRESETTKGAYCLSVSDFDNAKGLNVKHYKIRKLDSGGFYITSRTQFNSLQQLVAYYSKHAD GLCHRLTTVCPTSKPQTQGLAKDAWEIPRESLRLEVKLGQGCFGEVWMGTWNGTTRVAIK TLKPGTMSPEAFLQEAQVMKKLRHEKLVQLYAVVSEEPIYIVTEYMSKGSLLDFLKGETGKYL RLPQLVDMAAQIASGMAYVERMNYVHRDLRAANILVGENLVCKVADFGLARLIEDNEYTARQ GAKFPIKWTAPEAALYGRFTIKSDVWSFGILLTELTTKGRVPYPGMVNREVLDQVERGYRMP CPPECPESLHDLMCQCWRKEPEERPTFEYLQAFLEDYFTSTEPQYQPGENL

[0057] TABLE 2 Protein sequence of isoform 2 of human Src (SEQ ID NO. 2) MGSNKSKPKDASQRRRSLEPAENVHGAGGGAFPASQTPSKPASADGHRGPSAAFAPAAA EPKLFGGFNSSDTVTSPQRAGPLAGGVTTFVALYDYESRTETDLSFKKGERLQIVNNTEGD WWLAHSLSTGQTGYIPSNYVAPSDSIQAEEWYFGKITRRESERLLLNAENPRGTFLVRESET TKGAYCLSVSDFDNAKGLNVKHYKIRKLDSGGFYITSRTQFNSLQQLVAYYSKHADGLCHRL TTVCPTSKPQTQGLAKDAWEIPRESLRLEVKLGQGCFGEVWMGTWNGTTRVAIKTLKPGT MSPEAFLQEAQVMKKLRHEKLVQLYAVVSEEPIYIVTEYMSKGSLLDFLKGETGKYLRLPQL VDMAAQIASGMAYVERMNYVHRDLRAANILVGENLVCKVADFGLARLIEDNEYTARQGAKF PIKWTAPEAALYGRFTIKSDVWSFGILLTELTTKGRVPYPGMVNREVLDQVERGYRMPCPPE CPESLHDLMCQCWRKEPEERPTFEYLQAFLEDYFTSTEPQYQPGENL

[0058] TABLE 3 Sequence of mouse Src protein (SEQ ID NO. 3) MGSNKSKPKDASQRRRSLEPSENVHGAGGAFPASQTPSKPASADGHRGPSAAFVPPAAEP KLFGGFNSSDTVTSPQRAGALAGGVTTFVALYDYESRTETDLSFKKGERLQIVNNTRKDVR EGDWWLAHSLSTGQTGYIPSNYVAPSDSIQAEEWYFGKITRRESERLLLNAENPRGTFLVR ESETTKGAYCLSVSDFDNAKGLNVKHYKIRKLDSGGFYITSRTQFNSLQQLVAYYSKHADGL CHRLTTVCPTSKPQTQGLAKDAWEIPRESLRLEVKLGQGCFGEVWMGTWNGTTRVAIKTLK PGTMSPEAFLQEAQVMKKLRHEKLVQLYAVVSEEPIYIVTEYMNKGSLLDFLKGETGKYLRL PQLVDMSAQIASGMAYVERMNYVHRDLRAANILVGENLVCKVADFGLARLIEDNEYTARQG AKFPIKWTAPEAALYGRFTIKSDVWSFGILLTELTTKGRVPYPGMVNREVLDQVERGYRMPC PPECPESLHDLMCQCWRKEPEERPTFEYLQAFLEDYFTSTEPQYQPGENL

[0059] TABLE 4 cDNA sequence encoding human Scr protein (SEQ ID NO. 4) 1 catcgaggtt ttgagaggct aactctccca aaaaggacca tgggtagcaa caagagcaag 61 cccaaggatg ccagccagcg gcgccgcagc ctggagcccg ccgagaacgt gcacggcgct 121 ggcgggggcg ctttccccgc ctcgcagacc cccagcaagc cagcctcggc cgacggccac 181 cgcggcccca gcgcggcctt cgcccccgcg gccgccgagc ccaagctgtt cggaggcttc 241 aactcctcgg acaccgtcac ctccccgcag agggcgggcc cgctggccgg tggagtgacc 301 acctttgtgg ccctctatga ctatgagtct aggacggaga cagacctgtc cttcaagaaa 361 ggcgagcggc tccagattgt caacaacaca gagggagact ggtggctggc ccactcgctc 421 agcacaggac agacaggcta catccccagc aactacgtgg cgccctccga ctccatccag 481 gctgaggagt ggtattttgg caagatcacc agacgggagt cagagcggtt actgctcaat 541 gcagagaacc cgagagggac cttcctcgtg cgagaaagtg agaccacgaa aggtgcctac 601 tgcctctcag tgtctgactt cgacaacgcc aagggcctca acgtgaagca ctacaagatc 661 cgcaagctgg acagcggcgg cttctacatc acctcccgca cccagttcaa cagcctgcag 721 cagctggtgg cctactactc caaacacgcc gatggcctgt gccaccgcct caccaccgtg 781 tgccccacgt ccaagccgca gactcagggc ctggccaagg atgcctggga gatccctcgg 841 gagtcgctgc ggctggaggt caagctgggc cagggctgct ttggcgaggt gtggatgggg 901 acctggaacg gtaccaccag ggtggccatc aaaaccctga agcctggcac gatgtctcca 961 gaggccttcc tgcaggaggc ccaggtcatg aagaagctga ggcatgagaa gctggtgcag 1021 ttgtatgctg tggtttcaga ggagcccatt tacatcgtca cggagtacat gagcaagggg 1081 agtttgctgg actttctcaa gggggagaca ggcaagtacc tgcggctgcc tcagctggtg 1141 gacatggctg ctcagatcgc ctcaggcatg gcgtacgtgg agcggatgaa ctacgtccac 1201 cgggaccttc gtgcagccaa catcctggtg ggagagaacc tggtgtgcaa agtggccgac 1261 tttgggctgg ctcggctcat tgaagacaat gagtacacgg cgcggcaagg tgccaaattc 1321 cccatcaagt ggacggctcc agaagctgcc ctctatggcc gcttcaccat caagtcggac 1381 gtgtggtcct tcgggatcct gctgactgag ctcaccacaa agggacgggt gccctaccct 1441 gggatggtga accgcgaggt gctggaccag gtggagcggg gctaccggat gccctgcccg 1501 ccggagtgtc ccgagtccct gcacgacctc atgtgccagt gctggcggaa ggagcctgag 1561 gagcggccca ccttcgagta cctgcaggcc ttcctggagg actacttcac gtccaccgag 1621 ccccagtacc agcccgggga gaacctctag gcacaggcgg gcccagaccg gcttctcggc 1681 ttggatcctg ggctgggtgg cccctgtctc ggggcttgcc ccactctgcc tgcctgctgt 1741 tggtcctctc tctgtggggc tgaattgcca ggggcgaggc ccttcctctt tggtggcatg 1801 gaaggggctt ctggacctag ggtggcctga gagggcggtg ggtatgcgag accagcacgg 1861 tgactctgtc cagctcccgc tgtggccgca cgcctctccc tgcactccct cctggagctc 1921 tgtgggtctc tggaagagga accaggagaa gggctggggc cggggctgag ggtgcccttt 1981 tccagcctca gcctactccg ctcactgaac tccttcccca cttctgtgcc acccccggtc 2041 tatgtcgaga gctggccaaa gagcctttcc aaagaggagc gatgggcccc tggccccgcc 2101 tgcctgccac cctgcccctt gccatccatt ctggaaacac ctgtaggcag aggctgccga 2161 gacagaccct ctgccgctgc ttccaggctg ggcagcacaa ggccttgcct ggcctgatga 2221 tggtgggtgg gtgggatgag taccccctca aaccctgccc tccttagacc tgagggaccc 2281 ttcgagatca tcacttcctt gcccccattt cacccatggg gagacagttg agagcgggga 2341 tgtgacatgc ccaaggccac ggagcagttc agagtggagg cgggcttgga acccggtgct 2401 ccctctgtca tcctcaggaa ccaacaattc gtcggaggca tcatggaaag actgggacag 2461 cccaggaaac aaggggtctg aggatgcatt cgagatggca gattcccact gccgctgccc 2521 gctcagccca gctgttggga acagcatgga ggcagatgtg gggctgagct ggggaatcag 2581 ggtaaaaggt gcaggtgtgg agagagaggc ttcaatcggc ttgtgggtga tgtttgacct 2641 tcagagccag ccggctatga aagggagcga gcccctcggc tctggaggca atcaagcaga 2701 catagaagag ccaagagtcc aggaggccct ggtcctggcc tccttccccg tactttgtcc 2761 cgtggcattt caattcctgg ccctgttctc ctccccaagt cggcaccctt taactcatga 2821 ggagggaaaa gagtgcctaa gcgggggtga aagaggacgt gttacccact gccatgcacc 2881 aggactggct gtgtaacctt gggtggcccc tgctgtctct ctgggctgca gagtctgccc 2941 cacatgtggc catggcctct gcaactgctc agctctggtc caggccctgt ggcaggacac 3001 acatggtgag cctagccctg ggacatcagg agactgggct ctggctctgt tcggcctttg 3061 ggtgtgtggt ggattctccc tgggcctcag tgtgcccatc tgtaaagggg cagctgacag 3121 tttgtggcat cttgccaagg gtccctgtgt gtgtgtatgt gtgtgcatgt gtgcgtgtct 3181 ccatgtgcgt ccatatttaa catgtaaaaa tgtccccccc gctccgtccc ccaaacatgt 3241 tgtacatttc accatggccc cctcatcata gcaataacat tcccactgcc aggggttctt 3301 gagccagcca ggccctgcca gtggggaagg aggccaagca gtgcctgcct atgaaatttc 3361 aacttttcct ttcatacgtc tttattaccc aagtcttctc ccgtccattc cagtcaaatc 3421 tgggctcact caccccagcg agctctcaaa tccctctcca actgcctaag gccctttgtg 3481 taaggtgtct taatactgtc cttttttttt ttttaacagt gttttgtaga tttcagatga 3541 ctatgcagag gcctggggga cccctggctc tgggccgggc ctggggctcc gaaattccaa 3601 ggcccagact tgcggggggt gggggggtat ccagaattgg ttgtaaatac tttgcatatt 3661 gtctgattaa acacaaacag acctcagaaa aaaaaaaaaa aaaaaaaaaa a

[0060] TABLE 5 Mouse Src cDNA sequence (SEQ ID NO. 5) 1 atgggcagca acaagagcaa gcccaaggac gccagccagc ggcgccgcag cctggagccc 61 tcggaaaacg tgcacggggc agggggcgcc ttcccggcct cacagacacc gagcaagccc 121 gcctccgccg acggccaccg cgggcccagc gccgccttcg tgccgcccgc ggccgagccc 181 aagctcttcg gaggcttcaa ctcctcggac accgtcacct ccccgcagag ggcgggcgct 241 ctggcaggtg gggtgaccac ctttgtggcc ctctatgact atgagtcacg gacagagact 301 gacctgtcct tcaagaaagg ggagcggctg cagattgtca ataacacgag gaaggtggat 361 gtcagagagg gagactggtg gctggcacac tcgctgagca cgggacagac cggttacatc 421 cccagcaact atgtggcgcc ctccgactcc atccaggctg aggagtggta ctttggcaag 481 atcactagac gggaatcaga gcggctgctg ctcaacgccg agaacccgag agggaccttc 541 ctcgtgaggg agagtgagac cacaaaaggt gcctactgcc tctctgtatc cgacttcgac 601 aatgccaagg gcctaaatgt gaaacactac aagatccgca agctggacag cggcggtttc 661 tacatcacct cccgcaccca gttcaacagc ctgcagcagc tcgtggctta ctactccaaa 721 catgctgatg gcctgtgtca ccgcctcact accgtatgtc ccacatccaa gcctcagacc 781 cagggattgg ccaaggatgc gtgggagatc ccccgggagt ccctgcggct ggaggtcaag 841 ctgggccagg gttgcttcgg agaggtgtgg atggggacct ggaacggcac cacgagggtt 901 gccatcaaaa ctctgaagcc aggcaccatg tccccagagg ccttcctgca ggaggcccaa 961 gtcatgaaga aactgaggca cgagaaactg gtgcagctgt atgctgtggt gtcggaagaa 1021 cccatttaca ttgtgacaga gtacatgaac aaggggagtc tgctggactt tctcaagggg 1081 gaaacgggca aatatttgcg gctaccccag ctggtggaca tgtctgctca gatcgcttca 1141 ggcatggcct atgtggagcg gatgaactat gtgcaccggg accttcgagc cgccaatatc 1201 ctagtagggg agaacctggt gtgcaaagtg gccgactttg ggttggcccg gctcatagaa 1261 gacaacgaat acacagcccg gcaaggtgcc aaattcccca tcaagtggac cgcccctgaa 1321 gctgctctgt acggcaggtt caccatcaag tcggatgtgt ggtcctttgg gattctgctg 1381 accgagctca ccactaaggg aagagtgccc tatcctggga tggtgaaccg tgaggttctg 1441 gaccaggtgg agcggggcta ccggatgcct tgtccccccg agtgccccga gtccctgcat 1501 gaccttatgt gccagtgctg gcggaaggag cccgaggagc ggcccacctt cgagtacctg 1561 caggccttcc tggaagacta ctttacgtcc actgagccac agtaccagcc cggggagaac 1621 ctatag

[0061]

1 5 1 542 PRT Homo sapiens 1 Met Gly Ser Asn Lys Ser Lys Pro Lys Asp Ala Ser Gln Arg Arg Arg 1 5 10 15 Ser Leu Glu Pro Ala Glu Asn Val His Gly Ala Gly Gly Gly Ala Phe 20 25 30 Pro Ala Ser Gln Thr Pro Ser Lys Pro Ala Ser Ala Asp Gly His Arg 35 40 45 Gly Pro Ser Ala Ala Phe Ala Pro Ala Ala Ala Glu Pro Lys Leu Phe 50 55 60 Gly Gly Phe Asn Ser Ser Asp Thr Val Thr Ser Pro Gln Arg Ala Gly 65 70 75 80 Pro Leu Ala Gly Gly Val Thr Thr Phe Val Ala Leu Tyr Asp Tyr Glu 85 90 95 Ser Arg Thr Glu Thr Asp Leu Ser Phe Lys Lys Gly Glu Arg Leu Gln 100 105 110 Ile Val Asn Asn Thr Arg Lys Val Asp Val Arg Glu Gly Asp Trp Trp 115 120 125 Leu Ala His Ser Leu Ser Thr Gly Gln Thr Gly Tyr Ile Pro Ser Asn 130 135 140 Tyr Val Ala Pro Ser Asp Ser Ile Gln Ala Glu Glu Trp Tyr Phe Gly 145 150 155 160 Lys Ile Thr Arg Arg Glu Ser Glu Arg Leu Leu Leu Asn Ala Glu Asn 165 170 175 Pro Arg Gly Thr Phe Leu Val Arg Glu Ser Glu Thr Thr Lys Gly Ala 180 185 190 Tyr Cys Leu Ser Val Ser Asp Phe Asp Asn Ala Lys Gly Leu Asn Val 195 200 205 Lys His Tyr Lys Ile Arg Lys Leu Asp Ser Gly Gly Phe Tyr Ile Thr 210 215 220 Ser Arg Thr Gln Phe Asn Ser Leu Gln Gln Leu Val Ala Tyr Tyr Ser 225 230 235 240 Lys His Ala Asp Gly Leu Cys His Arg Leu Thr Thr Val Cys Pro Thr 245 250 255 Ser Lys Pro Gln Thr Gln Gly Leu Ala Lys Asp Ala Trp Glu Ile Pro 260 265 270 Arg Glu Ser Leu Arg Leu Glu Val Lys Leu Gly Gln Gly Cys Phe Gly 275 280 285 Glu Val Trp Met Gly Thr Trp Asn Gly Thr Thr Arg Val Ala Ile Lys 290 295 300 Thr Leu Lys Pro Gly Thr Met Ser Pro Glu Ala Phe Leu Gln Glu Ala 305 310 315 320 Gln Val Met Lys Lys Leu Arg His Glu Lys Leu Val Gln Leu Tyr Ala 325 330 335 Val Val Ser Glu Glu Pro Ile Tyr Ile Val Thr Glu Tyr Met Ser Lys 340 345 350 Gly Ser Leu Leu Asp Phe Leu Lys Gly Glu Thr Gly Lys Tyr Leu Arg 355 360 365 Leu Pro Gln Leu Val Asp Met Ala Ala Gln Ile Ala Ser Gly Met Ala 370 375 380 Tyr Val Glu Arg Met Asn Tyr Val His Arg Asp Leu Arg Ala Ala Asn 385 390 395 400 Ile Leu Val Gly Glu Asn Leu Val Cys Lys Val Ala Asp Phe Gly Leu 405 410 415 Ala Arg Leu Ile Glu Asp Asn Glu Tyr Thr Ala Arg Gln Gly Ala Lys 420 425 430 Phe Pro Ile Lys Trp Thr Ala Pro Glu Ala Ala Leu Tyr Gly Arg Phe 435 440 445 Thr Ile Lys Ser Asp Val Trp Ser Phe Gly Ile Leu Leu Thr Glu Leu 450 455 460 Thr Thr Lys Gly Arg Val Pro Tyr Pro Gly Met Val Asn Arg Glu Val 465 470 475 480 Leu Asp Gln Val Glu Arg Gly Tyr Arg Met Pro Cys Pro Pro Glu Cys 485 490 495 Pro Glu Ser Leu His Asp Leu Met Cys Gln Cys Trp Arg Lys Glu Pro 500 505 510 Glu Glu Arg Pro Thr Phe Glu Tyr Leu Gln Ala Phe Leu Glu Asp Tyr 515 520 525 Phe Thr Ser Thr Glu Pro Gln Tyr Gln Pro Gly Glu Asn Leu 530 535 540 2 536 PRT Homo sapiens 2 Met Gly Ser Asn Lys Ser Lys Pro Lys Asp Ala Ser Gln Arg Arg Arg 1 5 10 15 Ser Leu Glu Pro Ala Glu Asn Val His Gly Ala Gly Gly Gly Ala Phe 20 25 30 Pro Ala Ser Gln Thr Pro Ser Lys Pro Ala Ser Ala Asp Gly His Arg 35 40 45 Gly Pro Ser Ala Ala Phe Ala Pro Ala Ala Ala Glu Pro Lys Leu Phe 50 55 60 Gly Gly Phe Asn Ser Ser Asp Thr Val Thr Ser Pro Gln Arg Ala Gly 65 70 75 80 Pro Leu Ala Gly Gly Val Thr Thr Phe Val Ala Leu Tyr Asp Tyr Glu 85 90 95 Ser Arg Thr Glu Thr Asp Leu Ser Phe Lys Lys Gly Glu Arg Leu Gln 100 105 110 Ile Val Asn Asn Thr Glu Gly Asp Trp Trp Leu Ala His Ser Leu Ser 115 120 125 Thr Gly Gln Thr Gly Tyr Ile Pro Ser Asn Tyr Val Ala Pro Ser Asp 130 135 140 Ser Ile Gln Ala Glu Glu Trp Tyr Phe Gly Lys Ile Thr Arg Arg Glu 145 150 155 160 Ser Glu Arg Leu Leu Leu Asn Ala Glu Asn Pro Arg Gly Thr Phe Leu 165 170 175 Val Arg Glu Ser Glu Thr Thr Lys Gly Ala Tyr Cys Leu Ser Val Ser 180 185 190 Asp Phe Asp Asn Ala Lys Gly Leu Asn Val Lys His Tyr Lys Ile Arg 195 200 205 Lys Leu Asp Ser Gly Gly Phe Tyr Ile Thr Ser Arg Thr Gln Phe Asn 210 215 220 Ser Leu Gln Gln Leu Val Ala Tyr Tyr Ser Lys His Ala Asp Gly Leu 225 230 235 240 Cys His Arg Leu Thr Thr Val Cys Pro Thr Ser Lys Pro Gln Thr Gln 245 250 255 Gly Leu Ala Lys Asp Ala Trp Glu Ile Pro Arg Glu Ser Leu Arg Leu 260 265 270 Glu Val Lys Leu Gly Gln Gly Cys Phe Gly Glu Val Trp Met Gly Thr 275 280 285 Trp Asn Gly Thr Thr Arg Val Ala Ile Lys Thr Leu Lys Pro Gly Thr 290 295 300 Met Ser Pro Glu Ala Phe Leu Gln Glu Ala Gln Val Met Lys Lys Leu 305 310 315 320 Arg His Glu Lys Leu Val Gln Leu Tyr Ala Val Val Ser Glu Glu Pro 325 330 335 Ile Tyr Ile Val Thr Glu Tyr Met Ser Lys Gly Ser Leu Leu Asp Phe 340 345 350 Leu Lys Gly Glu Thr Gly Lys Tyr Leu Arg Leu Pro Gln Leu Val Asp 355 360 365 Met Ala Ala Gln Ile Ala Ser Gly Met Ala Tyr Val Glu Arg Met Asn 370 375 380 Tyr Val His Arg Asp Leu Arg Ala Ala Asn Ile Leu Val Gly Glu Asn 385 390 395 400 Leu Val Cys Lys Val Ala Asp Phe Gly Leu Ala Arg Leu Ile Glu Asp 405 410 415 Asn Glu Tyr Thr Ala Arg Gln Gly Ala Lys Phe Pro Ile Lys Trp Thr 420 425 430 Ala Pro Glu Ala Ala Leu Tyr Gly Arg Phe Thr Ile Lys Ser Asp Val 435 440 445 Trp Ser Phe Gly Ile Leu Leu Thr Glu Leu Thr Thr Lys Gly Arg Val 450 455 460 Pro Tyr Pro Gly Met Val Asn Arg Glu Val Leu Asp Gln Val Glu Arg 465 470 475 480 Gly Tyr Arg Met Pro Cys Pro Pro Glu Cys Pro Glu Ser Leu His Asp 485 490 495 Leu Met Cys Gln Cys Trp Arg Lys Glu Pro Glu Glu Arg Pro Thr Phe 500 505 510 Glu Tyr Leu Gln Ala Phe Leu Glu Asp Tyr Phe Thr Ser Thr Glu Pro 515 520 525 Gln Tyr Gln Pro Gly Glu Asn Leu 530 535 3 541 PRT Murinae gen. sp. 3 Met Gly Ser Asn Lys Ser Lys Pro Lys Asp Ala Ser Gln Arg Arg Arg 1 5 10 15 Ser Leu Glu Pro Ser Glu Asn Val His Gly Ala Gly Gly Ala Phe Pro 20 25 30 Ala Ser Gln Thr Pro Ser Lys Pro Ala Ser Ala Asp Gly His Arg Gly 35 40 45 Pro Ser Ala Ala Phe Val Pro Pro Ala Ala Glu Pro Lys Leu Phe Gly 50 55 60 Gly Phe Asn Ser Ser Asp Thr Val Thr Ser Pro Gln Arg Ala Gly Ala 65 70 75 80 Leu Ala Gly Gly Val Thr Thr Phe Val Ala Leu Tyr Asp Tyr Glu Ser 85 90 95 Arg Thr Glu Thr Asp Leu Ser Phe Lys Lys Gly Glu Arg Leu Gln Ile 100 105 110 Val Asn Asn Thr Arg Lys Val Asp Val Arg Glu Gly Asp Trp Trp Leu 115 120 125 Ala His Ser Leu Ser Thr Gly Gln Thr Gly Tyr Ile Pro Ser Asn Tyr 130 135 140 Val Ala Pro Ser Asp Ser Ile Gln Ala Glu Glu Trp Tyr Phe Gly Lys 145 150 155 160 Ile Thr Arg Arg Glu Ser Glu Arg Leu Leu Leu Asn Ala Glu Asn Pro 165 170 175 Arg Gly Thr Phe Leu Val Arg Glu Ser Glu Thr Thr Lys Gly Ala Tyr 180 185 190 Cys Leu Ser Val Ser Asp Phe Asp Asn Ala Lys Gly Leu Asn Val Lys 195 200 205 His Tyr Lys Ile Arg Lys Leu Asp Ser Gly Gly Phe Tyr Ile Thr Ser 210 215 220 Arg Thr Gln Phe Asn Ser Leu Gln Gln Leu Val Ala Tyr Tyr Ser Lys 225 230 235 240 His Ala Asp Gly Leu Cys His Arg Leu Thr Thr Val Cys Pro Thr Ser 245 250 255 Lys Pro Gln Thr Gln Gly Leu Ala Lys Asp Ala Trp Glu Ile Pro Arg 260 265 270 Glu Ser Leu Arg Leu Glu Val Lys Leu Gly Gln Gly Cys Phe Gly Glu 275 280 285 Val Trp Met Gly Thr Trp Asn Gly Thr Thr Arg Val Ala Ile Lys Thr 290 295 300 Leu Lys Pro Gly Thr Met Ser Pro Glu Ala Phe Leu Gln Glu Ala Gln 305 310 315 320 Val Met Lys Lys Leu Arg His Glu Lys Leu Val Gln Leu Tyr Ala Val 325 330 335 Val Ser Glu Glu Pro Ile Tyr Ile Val Thr Glu Tyr Met Asn Lys Gly 340 345 350 Ser Leu Leu Asp Phe Leu Lys Gly Glu Thr Gly Lys Tyr Leu Arg Leu 355 360 365 Pro Gln Leu Val Asp Met Ser Ala Gln Ile Ala Ser Gly Met Ala Tyr 370 375 380 Val Glu Arg Met Asn Tyr Val His Arg Asp Leu Arg Ala Ala Asn Ile 385 390 395 400 Leu Val Gly Glu Asn Leu Val Cys Lys Val Ala Asp Phe Gly Leu Ala 405 410 415 Arg Leu Ile Glu Asp Asn Glu Tyr Thr Ala Arg Gln Gly Ala Lys Phe 420 425 430 Pro Ile Lys Trp Thr Ala Pro Glu Ala Ala Leu Tyr Gly Arg Phe Thr 435 440 445 Ile Lys Ser Asp Val Trp Ser Phe Gly Ile Leu Leu Thr Glu Leu Thr 450 455 460 Thr Lys Gly Arg Val Pro Tyr Pro Gly Met Val Asn Arg Glu Val Leu 465 470 475 480 Asp Gln Val Glu Arg Gly Tyr Arg Met Pro Cys Pro Pro Glu Cys Pro 485 490 495 Glu Ser Leu His Asp Leu Met Cys Gln Cys Trp Arg Lys Glu Pro Glu 500 505 510 Glu Arg Pro Thr Phe Glu Tyr Leu Gln Ala Phe Leu Glu Asp Tyr Phe 515 520 525 Thr Ser Thr Glu Pro Gln Tyr Gln Pro Gly Glu Asn Leu 530 535 540 4 3711 DNA Homo sapiens 4 catcgaggtt ttgagaggct aactctccca aaaaggacca tgggtagcaa caagagcaag 60 cccaaggatg ccagccagcg gcgccgcagc ctggagcccg ccgagaacgt gcacggcgct 120 ggcgggggcg ctttccccgc ctcgcagacc cccagcaagc cagcctcggc cgacggccac 180 cgcggcccca gcgcggcctt cgcccccgcg gccgccgagc ccaagctgtt cggaggcttc 240 aactcctcgg acaccgtcac ctccccgcag agggcgggcc cgctggccgg tggagtgacc 300 acctttgtgg ccctctatga ctatgagtct aggacggaga cagacctgtc cttcaagaaa 360 ggcgagcggc tccagattgt caacaacaca gagggagact ggtggctggc ccactcgctc 420 agcacaggac agacaggcta catccccagc aactacgtgg cgccctccga ctccatccag 480 gctgaggagt ggtattttgg caagatcacc agacgggagt cagagcggtt actgctcaat 540 gcagagaacc cgagagggac cttcctcgtg cgagaaagtg agaccacgaa aggtgcctac 600 tgcctctcag tgtctgactt cgacaacgcc aagggcctca acgtgaagca ctacaagatc 660 cgcaagctgg acagcggcgg cttctacatc acctcccgca cccagttcaa cagcctgcag 720 cagctggtgg cctactactc caaacacgcc gatggcctgt gccaccgcct caccaccgtg 780 tgccccacgt ccaagccgca gactcagggc ctggccaagg atgcctggga gatccctcgg 840 gagtcgctgc ggctggaggt caagctgggc cagggctgct ttggcgaggt gtggatgggg 900 acctggaacg gtaccaccag ggtggccatc aaaaccctga agcctggcac gatgtctcca 960 gaggccttcc tgcaggaggc ccaggtcatg aagaagctga ggcatgagaa gctggtgcag 1020 ttgtatgctg tggtttcaga ggagcccatt tacatcgtca cggagtacat gagcaagggg 1080 agtttgctgg actttctcaa gggggagaca ggcaagtacc tgcggctgcc tcagctggtg 1140 gacatggctg ctcagatcgc ctcaggcatg gcgtacgtgg agcggatgaa ctacgtccac 1200 cgggaccttc gtgcagccaa catcctggtg ggagagaacc tggtgtgcaa agtggccgac 1260 tttgggctgg ctcggctcat tgaagacaat gagtacacgg cgcggcaagg tgccaaattc 1320 cccatcaagt ggacggctcc agaagctgcc ctctatggcc gcttcaccat caagtcggac 1380 gtgtggtcct tcgggatcct gctgactgag ctcaccacaa agggacgggt gccctaccct 1440 gggatggtga accgcgaggt gctggaccag gtggagcggg gctaccggat gccctgcccg 1500 ccggagtgtc ccgagtccct gcacgacctc atgtgccagt gctggcggaa ggagcctgag 1560 gagcggccca ccttcgagta cctgcaggcc ttcctggagg actacttcac gtccaccgag 1620 ccccagtacc agcccgggga gaacctctag gcacaggcgg gcccagaccg gcttctcggc 1680 ttggatcctg ggctgggtgg cccctgtctc ggggcttgcc ccactctgcc tgcctgctgt 1740 tggtcctctc tctgtggggc tgaattgcca ggggcgaggc ccttcctctt tggtggcatg 1800 gaaggggctt ctggacctag ggtggcctga gagggcggtg ggtatgcgag accagcacgg 1860 tgactctgtc cagctcccgc tgtggccgca cgcctctccc tgcactccct cctggagctc 1920 tgtgggtctc tggaagagga accaggagaa gggctggggc cggggctgag ggtgcccttt 1980 tccagcctca gcctactccg ctcactgaac tccttcccca cttctgtgcc acccccggtc 2040 tatgtcgaga gctggccaaa gagcctttcc aaagaggagc gatgggcccc tggccccgcc 2100 tgcctgccac cctgcccctt gccatccatt ctggaaacac ctgtaggcag aggctgccga 2160 gacagaccct ctgccgctgc ttccaggctg ggcagcacaa ggccttgcct ggcctgatga 2220 tggtgggtgg gtgggatgag taccccctca aaccctgccc tccttagacc tgagggaccc 2280 ttcgagatca tcacttcctt gcccccattt cacccatggg gagacagttg agagcgggga 2340 tgtgacatgc ccaaggccac ggagcagttc agagtggagg cgggcttgga acccggtgct 2400 ccctctgtca tcctcaggaa ccaacaattc gtcggaggca tcatggaaag actgggacag 2460 cccaggaaac aaggggtctg aggatgcatt cgagatggca gattcccact gccgctgccc 2520 gctcagccca gctgttggga acagcatgga ggcagatgtg gggctgagct ggggaatcag 2580 ggtaaaaggt gcaggtgtgg agagagaggc ttcaatcggc ttgtgggtga tgtttgacct 2640 tcagagccag ccggctatga aagggagcga gcccctcggc tctggaggca atcaagcaga 2700 catagaagag ccaagagtcc aggaggccct ggtcctggcc tccttccccg tactttgtcc 2760 cgtggcattt caattcctgg ccctgttctc ctccccaagt cggcaccctt taactcatga 2820 ggagggaaaa gagtgcctaa gcgggggtga aagaggacgt gttacccact gccatgcacc 2880 aggactggct gtgtaacctt gggtggcccc tgctgtctct ctgggctgca gagtctgccc 2940 cacatgtggc catggcctct gcaactgctc agctctggtc caggccctgt ggcaggacac 3000 acatggtgag cctagccctg ggacatcagg agactgggct ctggctctgt tcggcctttg 3060 ggtgtgtggt ggattctccc tgggcctcag tgtgcccatc tgtaaagggg cagctgacag 3120 tttgtggcat cttgccaagg gtccctgtgt gtgtgtatgt gtgtgcatgt gtgcgtgtct 3180 ccatgtgcgt ccatatttaa catgtaaaaa tgtccccccc gctccgtccc ccaaacatgt 3240 tgtacatttc accatggccc cctcatcata gcaataacat tcccactgcc aggggttctt 3300 gagccagcca ggccctgcca gtggggaagg aggccaagca gtgcctgcct atgaaatttc 3360 aacttttcct ttcatacgtc tttattaccc aagtcttctc ccgtccattc cagtcaaatc 3420 tgggctcact caccccagcg agctctcaaa tccctctcca actgcctaag gccctttgtg 3480 taaggtgtct taatactgtc cttttttttt ttttaacagt gttttgtaga tttcagatga 3540 ctatgcagag gcctggggga cccctggctc tgggccgggc ctggggctcc gaaattccaa 3600 ggcccagact tgcggggggt gggggggtat ccagaattgg ttgtaaatac tttgcatatt 3660 gtctgattaa acacaaacag acctcagaaa aaaaaaaaaa aaaaaaaaaa a 3711 5 1626 DNA Murinae gen. sp. 5 atgggcagca acaagagcaa gcccaaggac gccagccagc ggcgccgcag cctggagccc 60 tcggaaaacg tgcacggggc agggggcgcc ttcccggcct cacagacacc gagcaagccc 120 gcctccgccg acggccaccg cgggcccagc gccgccttcg tgccgcccgc ggccgagccc 180 aagctcttcg gaggcttcaa ctcctcggac accgtcacct ccccgcagag ggcgggcgct 240 ctggcaggtg gggtgaccac ctttgtggcc ctctatgact atgagtcacg gacagagact 300 gacctgtcct tcaagaaagg ggagcggctg cagattgtca ataacacgag gaaggtggat 360 gtcagagagg gagactggtg gctggcacac tcgctgagca cgggacagac cggttacatc 420 cccagcaact atgtggcgcc ctccgactcc atccaggctg aggagtggta ctttggcaag 480 atcactagac gggaatcaga gcggctgctg ctcaacgccg agaacccgag agggaccttc 540 ctcgtgaggg agagtgagac cacaaaaggt gcctactgcc tctctgtatc cgacttcgac 600 aatgccaagg gcctaaatgt gaaacactac aagatccgca agctggacag cggcggtttc 660 tacatcacct cccgcaccca gttcaacagc ctgcagcagc tcgtggctta ctactccaaa 720 catgctgatg gcctgtgtca ccgcctcact accgtatgtc ccacatccaa gcctcagacc 780 cagggattgg ccaaggatgc gtgggagatc ccccgggagt ccctgcggct ggaggtcaag 840 ctgggccagg gttgcttcgg agaggtgtgg atggggacct ggaacggcac cacgagggtt 900 gccatcaaaa ctctgaagcc aggcaccatg tccccagagg ccttcctgca ggaggcccaa 960 gtcatgaaga aactgaggca cgagaaactg gtgcagctgt atgctgtggt gtcggaagaa 1020 cccatttaca ttgtgacaga gtacatgaac aaggggagtc tgctggactt tctcaagggg 1080 gaaacgggca aatatttgcg gctaccccag ctggtggaca tgtctgctca gatcgcttca 1140 ggcatggcct atgtggagcg gatgaactat gtgcaccggg accttcgagc cgccaatatc 1200 ctagtagggg agaacctggt gtgcaaagtg gccgactttg ggttggcccg gctcatagaa 1260 gacaacgaat acacagcccg gcaaggtgcc aaattcccca tcaagtggac cgcccctgaa 1320 gctgctctgt acggcaggtt caccatcaag tcggatgtgt ggtcctttgg gattctgctg 1380 accgagctca ccactaaggg aagagtgccc tatcctggga tggtgaaccg tgaggttctg 1440 gaccaggtgg agcggggcta ccggatgcct tgtccccccg agtgccccga gtccctgcat 1500 gaccttatgt gccagtgctg gcggaaggag cccgaggagc ggcccacctt cgagtacctg 1560 caggccttcc tggaagacta ctttacgtcc actgagccac agtaccagcc cggggagaac 1620 ctatag 1626 

what is claimed is:
 1. A method for identifying a therapeutic compound for the treatment of Alzheimer's disease comprising the step of identifying a Src protein inhibitor.
 2. The method of claim 1 wherein said identifying step comprises the steps of: a) providing a reporter gene operatively linked to a regulatory nucleotide sequence, wherein said regulatory nucleotide sequence regulates Src protein expression; b) introducing a candidate compound; and c) measuring the activity of said reporter gene in response to said candidate compound.
 3. The method of claim 2 wherein said reporter gene is Src.
 4. The method of claim 2, wherein said regulatory nucleotide sequence is the Src promoter.
 5. The method of claim 2 wherein said regulatory nucleotide sequence regulates a Src protein selected from the group consisting of: human Src and mouse Src.
 6. The method of claim 1 wherein said Src protein is selected from the group consisting of: human Src and mouse Src.
 7. The method of claim 1, wherein said Src protein comprises an amino acid sequence selected from the group consisting of: SEQ ID NO:1, SEQ ID NO:2, and SEQ ID NO:3.
 8. The method of claim 1, comprising the steps of: a) providing at least one mammalian cell expressing said Src protein; b) introducing a candidate compound to said mammalian cell; and c) measuring the activity of said Src protein in response to said candidate compound. 9 The method of claim 8, wherein said providing step (a) comprises providing a primary cell culture of neurons. 10 A therapeutic compound identified by the method of claim
 1. 11 A pharmaceutical composition comprising an effective amount of the therapeutic compound of claim 10 and a pharmaceutically acceptable excipient. 12 A method for treating Alzheimer's disease comprising the step of administering the pharmaceutical composition of claim
 11. 13. A pharmaceutical composition comprising an effective amount of PP2 and a pharmaceutically acceptable excipient.
 14. A method for treating Alzheimer's disease comprising the step of administering the pharmaceutical composition of claim
 13. 